trigger updating函数带参数用法;

1.表

SQL> desc a

Name   Type    Nullable Default Comments
------ ------- -------- ------- --------
ID_    INTEGER Y                         
COUNT_ INTEGER Y                         

 

2.建立触发器

create or replace trigger tri_a
before delete or update or delete on a
for each row
declare
  errno  number;
  errmsg varchar2(30);
  wrong_error exception;
begin
  if updating('COUNT_') then
    errno  := '-20030';
    errmsg := '哈哈，不允许更新此列';
    raise wrong_error;
  end if;
exception
  when wrong_error then
    raise_application_error(errno, errmsg);
end;

----------------------

3.进行update操作

SQL> select * from a;
 
                                    ID_                                  COUNT_
--------------------------------------- ---------------------------------------
                                      1                                      10
                                      3                                       6
                                      2                                       4
                                      3                                       4
                                      5                                       5
 

SQL> update a set count_=99 where id_=5;
 
update a set count_=99 where id_=5
 
ORA-20030: 哈哈，不允许更新此列
ORA-06512: at "AIKI.TRI_A", line 13
ORA-04088: error during execution of trigger 'AIKI.TRI_A'

最后

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